The invention relates to a method for determining an engagement point of a hybrid clutch of a hybrid vehicle, which is actuated by a hydrostatic clutch actuator, with the hybrid clutch separating or connecting an internal combustion engine and an electric traction drive, and when the internal combustion engine is off, the engagement point is determined by slowly operating the hybrid clutch, starting with a position of the hybrid clutch which it assumes in a disconnected state, while monitoring the torque of the electric traction drive when a defined increase in torque is detected, as well as a device for implementing the method.
DE 10 2010 024 941 A1 discloses a method for controlling a duplex clutch with at least two partial drivetrains, each of which potentially being coupled via a clutch to the internal combustion engine. During drive operation of the vehicle comprising the duplex clutch transmission, an engagement point of the clutch is determined independently from the torque of the motor. This engagement point is here determined during the start of the vehicular operation and then adapted during the operation of the vehicle.
In a hybrid vehicle with a hybrid drivetrain the driving resistance can be overcome by two independent energy sources, such as using fuel of an internal combustion engine and electric energy from a traction battery of an electric engine, by way of converting them into mechanical energy. According to DE 10 2008 030 473 A1 a method is known for determining an engagement point of an automatic hybrid clutch in a hybrid drivetrain. The engagement point of the hybrid clutch arranged between an internal combustion engine and an electric traction drive is determined when the combustion engine is off by slowly closing the hybrid clutch and evaluating the influence of the closing hybrid clutch upon the electric machine of the electric traction drive which rotates with a predetermined speed. This hybrid clutch allows in the open state a purely electric driving of the hybrid vehicle, while in the closed state the torque of the internal combustion engine is transferred to the driving wheel.